CMYK is a color model of the four colors, cyan, magenta, yellow and black. The CMYK model works by partially or entirely masking certain colors of a light or white background (that is, absorbing and scattering particular wavelengths of light). Thus, white is the natural color of the background while black results from a full combination of the colors. Deeper black tones and unsaturated and dark colors can be produced by substituting black for the combination of cyan, magenta and yellow. CMYK is an example of a model called, “subtractive,” because colors subtract brightness and colors from a light or white background. Photocopies or prints, such as, a print on paper, are examples of display modes that are based on a subtractive color model as generally the image is presented on a lighter background, such as, white paper.
An alternative way to generate color is an additive model, such as, RGB (red, green and blue), wherein the combination of all colors produces white, and black is the absence of all light. CRT's, LCD's, televisions and so on are examples of display modes that are based on an additive color model as generally the image is presented on a darker surface.
The prevalent use of red colors makes red toners desirable, particularly the red colors found in the PANTONE® color space, Red 032 and Warm Red, which are similar in hue.
However, there are limitations in reproducing certain colors and in reproducing colors that are similar in hue. Moreover, color characteristics can change depending, for example, on the medium bearing or presenting the colors; the ancillary or accessory ingredients in a composition containing a colorant, such as, a dye, a pigment or a lake pigment; the compatibility of some colorants with a manufacturing process or reagents used therein, such as, a particular ink-producing process and the reagents used therein; and so on.
Therefore, it is desirable to have red toners for use, for example, in color imaging to complement existing toners and to enable a wider and more accurate range of red colors and hues.